[Effect of different isoforms of tocopherols on expression of intercellular adhesion molecule-1 in human umbilical...

To observe the influence of different tocopherol isoforms on oxidized low density lipoprotein (oxLDL) or recombinant human C-reactive protein (rhCRP)-induced expression of intercellular adhesion molecule-1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) and to investigate the potential mechanisms and effects of different tocopherols on atherosclerosis.

Cultured HUVECs were incubated with oxLDL, oxLDL + alpha-tocopherol, oxLDL + gamma-tocopherol, oxLDL + mixed-tocopherols, rhCRP, rhCRP + alpha-tocopherol, rhCRP + gamma-tocopherol rhCRP + mixed-tocopherols for 24 hours, respectively. The ICAM-1 expressions of protein and mRNA were detected by cell enzyme linked immunosorbent assay (ELISA), flow cytometric technique and RT-PCR.

Incubation of HUVECs with oxLDL or rhCRP for 24 hours significantly increased ICAM-1 expressions of proteins and mRNA. The different tocopherols inhibited oxLDL-induced ICAM-1 expression in HUVECs in a concentration-dependent manner (50-200 micromol/L) and mixed-tocopherols were more potent than alpha-tocopherol or gamma-tocopherol alone. However, rhCRP-induced ICAM-1 expression in HUVECs was not inhibited by tocopherols.

The different tocopherols inhibited oxLDL-induced ICAM-1 expression in HUVECs and mixed-tocopherols were more potent than alpha-tocopherol or gamma-tocopherol alone, which may be important for the beneficial effects of tocopherols on atherosclerosis and cardiovascular disease.